Unitary control for condensers



July 26, 1932. M. B. WEST ET AL 1,868,553

UNITARY CONTROL FOR CONDENSERS Original Filed Dec. 9, 1926 2 Sheets-Sheet 1 July 26, 1932. M. B. WEST ET AL 1,868,553

UNITARY CONTROL FOR CONDENSERS 4 Original Filed Dec. 9, 1926 2 Sheets-Sheet 2 Patented July 26, 1932 STATES PATENT OFFICE MAI RIO B. VJEST, OF LIMA, AND HARRY G. MAIBOHM, OF SANIDUSKY, OHIO, ASSIGNORS TC 'SIMILEX RADIO COMPANY, OF SANDUSKY, OHIO, A CORPORATION OF OHIO UNITARY CONTROL FOR CONDENSERS Application filed December 9 1926, Serial No. 153,526. Renewed June 11, 1932.

dinarily"introduced in the radio frequency.

c rcuits of a radio receiving apparatus. I v

"Attempts have been made, at various times, top'rovide a means whereby a plurality of variable condensers could be controlled or operated simultaneously from asingle controlling member or dial, but they have been more orless ineihcient because ofthe tact-that the variable condcnser ot the first stage radio frequency amplification, or the variable condenser introduced into the antenna circuit, could not be adjusted'at the same rate of change of capacity as the variable condensers or" the remaining or following stages of radio irequency amplifying circuits. This was due to the fact that the normal capacity of the Y ri able condenser of the antenna circuit was increased by tie capacity of the antenna itself, so that the total capacity of the variable condenser of the first stage of radio frequency amplification was exceedingly greater than the capacihes ,ot the'variable condensers of the following stages of radio frequency amplification. Therefore, from the foregoing it will. be seen that an accurate tuning in could not be eii ected where the capacities of the variable condensers were normallythe same and where these variable condensers were adj usted simultaneously at the same rate a of change incapacity. By means or" this invention this objection has been overcome and it 15 possible to tune each circuit in resonance witheach oi the other circuits by the operation of a single selector member or dial.

It is a further object of the invention to provide separatemeans forvaryingthe capacity of the variablecondenser of the-first stage of radio frequency amplification so that a more accurate tuning in may be afforded,

the result being much clearer anda much more accurate reception.

to compensate for the added capacity of the antenna to the capacityot' the variable condn.v

of the first stage of radio frequency amplification, means 1S provided simultaneously.

Viith the objects above indicated and other objects hereinafter explained in View, our invention consists in the construction and combination of elements hereinafter described and claimed.

Referring to the drawings:

Fig. 1 is a frontelevational View of the disks with the panel removed except as to that portion including the graduations.

2 is a top plan view of the apparatus.

Fig. 3 is a bottom plan view showing the locationof the vernier condenser.

Fig. 4 is an enlarged front elevational view of the disk secured to the first condenser.

Fig. 5 is a bottom plan view of the disk shown in Fig. 4.: v

Fig. 6 is an enlarged front elevational view of the disk secured to the second condenser. Fig. 7 is a top plan view of the disk shown Fig. 8 is an enlarged front elevational view of the disk secured to the third condenser.

Fig. 9 is a top plan view of the disk shown in Fig. 8.

In the drawings, 10 represents the sub-base which is composed of suitable insulating material and adapted to support the various apparatus to which is secured,.at the front edge, a vertically extending insulated panel 11, while 12, shown in dotted lines, represents the panel positioned in front of the radio receiving apparatus. This panel 12 has etched thereon calibrations 13 which indicate the various wave lengths. Secured to the panel 11 by means of bolts or other suitable means, are condensers 14, 15 and 16 properly spaced apart. These condensers are provided with shaft 18 of the center condenser extends further outwardly than the shafts l7 "and '19 and through a suitable openinggin the 7 panel 12 and has secured to its outer end a 5 pointer'20 which co-operates with'the calibrations 13 onthe panel 12.

Av disk23 is provided along. its. outer pe-.

riphery with a groove 24 and a hub 25 having afcentral opening 26 therethrough. This hub 25 is pinned to theouter end of the shaft- 17 so that rotation "of the disk 28 causes the rotor plates ofthezcondenser 14 to rotate in thesame direction. 7 A disk 26 similar to the disk-"23,"isproyide'd. around its periphery,

witha.. groove 27..and ahub 28 having a cen tral ,opening28a. This hub 28 is plnned to the shaft l9rso that the rotor plates carried by theshaft l9.will.rotate simultaneously with the rotationof the disk 26. .A disk 29 of .a greater thickness than the disk .23 .or 26,-[is provided with peripheral paralleljgrooyes 305.31 and 32anrlan axially I extending hub 33 which has central'opensecured vtothje shaftlSlby a pin extending th'roughthe hub 33and the shaft 18 sot-hat ing 34 extending entirely through .thehub 33' and disk 29. This disk is interposedbetween the l pointer .20 and ,the vcondenser .15 and "is this disk .29 likewise rotates simultaneously with the .rotor' plates .of the "condenser 15.

The rotation of :this disk 29, however, is

' limitedby :theengagement of stops 35'and 86 with 'theupper edgeofth-e panelll, care being taken to locate orposition these stops so that when one or the other of the stops engage the upper edgeiof the panel lLthe rotor plates ofthe condenser l5are either entirely interleaving with the stator plates or entirely out of'engagement therewith. 7

.As has .been 'heretofore explained :in the objects 'it is necessary to provide forregulat' ing the capacity of condenser 14 so that there is a more rapid change incapacity taking place therein, than with thecond-ensers '15 and 16,.dueto th-e factthat the capacity of p a COUIItSIfClGClIWISG"CllYSCiJlOIl passes the I condenser 14 is substantially increased by the introduction of the antenna into the circuit of whichthis condenser 14 is'a; part. This increase .lntheichange of capacity in condenser 14 has, therefore, "been" provided by reducing "the external diameter of the d sk 23' w th..respectgtotheexternal diameters ofvthe disks'29 ,and'z26; the condensers here shownbein-g of certain maximum capacities.

i be substantial1y'3 in diameter;- Itis to'be understood,}however, that the relative diam-.1-

be secured the As a ineans for rotating the disks simultaneouslya cable arrangement has been eni- .ployed, the primary feature'of which is to .maintaina degree of tension upon the various cables between the adjacent disksso as to prevent any likelihood of slippage 0r variation between the rotation of the disks. lVith "the rotor plates or the condensers entirely out of engagement with thestator plates of the condensersas shownin 2, the disks 23,

V26 and29 :as'srunetherelativepositions shown in Figs..4, 6,.ai1d 8. Thedisk 23 is-provided with'anflangnlarly extending slot, 37 which extendsentirely.throu the disk, a spring 38* being disposed within theslot 87 and which has'onefendsecuredto the disk at39while the opposite end is secured to arable '40, preterably otfine piano wire or the like, which cable extends through an opening 41 in the disk 23', and is. received by the grooye- 24. This cable .40-extends into engagement with the grc'oreSO otthedisk 29 and theend passes n through an opening 42, and is looped over a pin at 43, .then 1 passes outward through opening 42,.continuing aroundj29 in the'sa me groove- 30,. extends into engagement. with groove-240i disk 23, continuing in the same direction around 23 .to an opening 41 through which itpasses to beseoured at 45 It will be seen jthatthiscable 40 is always under tension duete the action ofl the spring 38-thereon. p

The disk 26 is provided with-an elongated slot 47 extkendingonthe .o g iposit-e side of'the center frointhe slot. 37 in thedisk 23 but in. a

parallel.directionthereto. This slot 4? has disposed thereinva spring48 which has one endsecured =asindicated at 49 to the disk 26 while the opposite end is attached to acable 50,which extends through an opening 51 into and isseated.withinthegroove 2'Tand extends mto the {groove 310i? the drum. 29 in through an opening in'the disk 29 where it loops over. a p1n.at5l and outward through the same-opening,-followinggroove 31 of disk 7 29, until ithas encircled 0f-29, then extending ontodisk 26where-it engagesgroove -27, tollowmg around. in counterclockwise direction to an opening 51 through-whmh 1t passes. andfissecurely fastened to disk 26 at l-t-w ll berseen from the foregoing description that any rotation or movement of the shai 't 18 of the condenser 15 will cause a similar-movement cf the shafts 17 and 19 through the mediumot the cables and that these cables are prevented from slipping (within the iii grooves of the respectivedisks.,lbymeans; of the tension imposed therein. by the springs of the disks 23'and26, Y. I :x

,Direcitlybelow the'shaft, 18 of the condenser is a tubular sleeve'j54which extends through an. opening in the panel 12 and has its inner end journaledfwithin the panel 11. This sleeve. 54ccarries midway between the panelll and 12a grooved pulleywheel 55 se curely attached thereto] This pulley wheel 55 is positioned so that the groove 56 is directly beneath the groove 32 of the disk 29. This pulley wheel 55 'receives Within the groove 5 6 the cablefi? which extends counterclockwise around the disk 29 within the groove 32 having one end attachedto a spring 58 disposed within a slot59 formed at the lowerportionofthe disk-29 while the opposite end of. the spring 58iis secured to the disk 29 as indicated at 60. The opposite endofthis cable 57 extends throughfan opening provided inthe grooveof the disk 29 and is secured to the disk as indicated at 61. This sleeve54 has secured thereto, to the portion extending beyond the .panel 12, a knob 63 1'0-.

tation of which causes rotationof the sleeve 54 carry1ng the pulley Wheel seen, therefore, through the arrangement of cables heretoforev described that any rotary movementof the knob 63 will be imparted to the disk 29 which in turnill impart this retary .-m otion to the disks23-and 26. The disksQQ and 26 will rotate at the same rate of speed, due to the fact that the diameters of these disks areithe same,;but the rotation of the disk 23 will be more rapid in either direct on due to; the reduced diameter of the disk 28 with respect to thediametersof the disks 2Q and 26, the capacity of the condenser 14. therefore being changed more rapidly than the capacities of the remaining COIl',

densers.

justment the rotor of the first condenser 14 has one less plate than the rotors of there-- '63 and has secured to the extendin 0 end a knob 66lfor' permitting adjustment of the rotor plates with respect to thestator. This Vernier condenser is mounted on the panel 11 through the bracket which is riveted or otherwise securely fastened to the panel 11. This vernier condenser isprovided with the usualstatorterminal 68 and rotor terminal69 which. are connected by means of conductors to the V stator terminal 22 of thecondenser 14and the rotor terminal 21 respectively. It will, there- It will be.

fore, be seen from this arrangement that the capacity of the condenser 14 can be more minutely regulated than if an additional rotor plate were included with the rotor plates of the condenser 14.

In the operation of the device it is only necessary to rotate the knob 63 in either direction, dependin upon the desired wave length or station to be received, this rotation simultaneously and proportionately changing the capacities of the condensers for resonantly tuning in the incoming waves. When the desired station has been located and tuned in additional quality'or clearness may be obtained by the rotation of the knob 66 thereby adjusting the capacity of the Vernier c0ndenser which, being parallel with condenser 14, more finely adjusts the capacity of that condenser. Q

' Having thus described our invention, What we claim is: y

;1. In a radio receiving apparatus, a plurality of variable condensers, rotary control members for each of said condensers disposed in the same horizontal plane and means interconnecting said rotary control members for varying the capacities of said condensers simultaneously, the capacity of one of said condenscrs being more rapidly varied than the others, said means being resiliently attached to each of said rotary control members for synchronously moving said condensers.

2. In a radio receiving apparatus, a plurality of variable condensers, drive shafts for each of said condensers disposed in the same plane, a disk secured to the drive shaft of each of said condensers, cables resiliently interconnee-ting each of said disks, said cables being rigidly attached toone disk and flexibly attached tov the adjacent disk and a unitary operating member for imparting movement to u K said disks. To obtain a more dehcate and accurate ad- 3. In a radio receiving apparatus, a. plrrality of condensers, each provided with a rotatable shaft, said shafts belng disposed in the same plane, a disk secured to each of said shafts, cables fastened between the-adjacent disks, means interposed in said cables for sub- 1' ectin g said cables to tension intermediate said disks and a single control means connected to one of said disks for causing angular adjustment of .said disks.

4. In a radio receiving apparatus, a plurality of condensers, rotatable shafts on each con denser, said shafts being disposed in the same horizontal plane, disks on said shafts, one of I said disks being of reduced diameter, yieldable means disposed within the confines of certain of said disks, means extending from said yleldable means forconnecting said disks to-- gether to cause simultaneous angular move ment thereof, and a unitary actuating member 'for imparting simultaneous adjustment to said disks.- I y 5.;In a radio receivingapparatus, a plurality 'of condensers, rotatable shafts on each condenser, said shaftsbeing disposed the same horiz'ontal-plane;idiskszon said shafts,

0116301? said disks being; of reduced diameter,-

means connecting said; disks together'to'cause simultaneous angular movement thereof, a unitary: actuatlng fmember connected: to ,one

of said disks tor imparting angularadjust ment: to said shafts and tension-means :supported by certain of said disks, said tension means being disposed in series with said connecting means.

7 ztlg-lnaa-radio receiving apparatus, a plurality of variable condensers provided with rotatable shafts, grooved disks secured to said shatts,,tension cables engaging the grooves of saiddisks and permanently secured adjacent the peripheries of said disks and adapted to cause simultaneous rotation of "said" disks, a unitary operatingmember, and 'means between said member and :one of said disks wherebyvthe rotation of said operating member causes alike rotation of'saiddisks;

I 7. I-n'a radio receiving "apparatus, a pluwith a rotatable shaft, said shafts being disposed infthe-sztme:horizontal plane, adisk secured toeachshaft, one'of said disks being ofjlessdiameter' than adjacent disks, a cable connecting the disk ofless diameter with the adjacent :disk' and a cable connecting the adjacentidisk with adisk on the opposite side from the'disk'of'less diameter, a single operatingmember, a cable connected to said op-- eratmg' member and "oneof saiddisks so that rotation of said operating member causes a similar'rotation of said disks and coil springs extending chordal'to certain: of said disks,' each of said coilsprings being anconnected-at the other end to saidcable.

8. As an article of manufacture *aset of disks each provided with an opening adapted to be secured'to the rotary shafts of a plurality of variable condensers, onelof said disks being of-less diameter than adjacent disks, meanstor connecting said disks together the axesofsaid disks being aligned in the same horizontal plane for simultaneous angular movement, an operating'member, means for connecting. saidoperating member to one ofsaid disks certain of said disks having a recess extending substantially chordal thereofand' a spring disposed in the recess and LanchOred; at one end to said disk and at-the other end to saidconnecting means.

9. Ina radio receiving apparatus, a plura'lity of variable condensers each havinga rotary member adjustablefor varying the capaclties Y 'Of' SZI-Id condensers, said rotary members all being disposed in the same hori--' zontal plane, a single operating member tion thereto and simultaneously driving all or said rotary actuating shafts :win synchrosymmetrically arranged with respect to all of said rotary members for simultaneously varying the capacity of said condense'rs,=-and rality of variablelcondensers, each-provided chored .at'one end to its associated disk and" sociated'rotary member and connected-at its other end to said cables. I

10. Tuning apparatus comprising'a' multiplicity of condensers spaced one "from another and having actuating shaftsextending substantially parallel one'to' another, a drrving disk 'on'each of said actuating shafts, said driving disks each being-grooved at the peripheries thereof, flexible "drive means positively connected to said disks and moving inthe grooved peripheries thereof, tension means included in each of said flexible drive means,and aseparatelytensioned cord positively connected to one of said driving disks for shifting all of saiddriving 'diskssimultaneously for the unitary control of the several condensers connected'thereto.

l1. Tuning apparatus comprising-a multiplicity of variable"condensers'each having rotary actuating "shafts extending substantially parallel one to another, driving disks carried by each of said shafts, 'flexible'drive cords*positively interconnecting said driving disks, a resilientidevice carried by each of said driving disks 'for subjecting said driving cords totension, and a flexible driving "cord connected to one of "said driving disks for imparting motion thereto and 'simultaneously moving said'driving disksfor the unitary control of all of said'varia'ble condensers; c a

12. Tuning apparatus comprising ajmultiplicity' of variable impedance devices, rotary actuating shaftsconnected withsaid variable impedance devices and extending substantially parallel one to another, driving disks carried by each of said rotary actuating shafts-grooves in the peripheries of each of said driving disks, flexible'cords extending around the grooves of said disksand interconnecting selected disks, as spring-carried by each of 'said driving disks, each springhaving one end thereof anchoredLto the driving disk and the otherend'thereof connectedto one of the flexible cords for the 1positiveinterconnection ofsaid disks, and a I flexible 'eor'd fdrive connected with one of sa'idjdr'iving disks' for impartingrotary monism. Y

13. In a control system for radio broadcast receivers, a multiplicity of independent Variable tuning devices, rotatable shafts for each of said devices, a pulley member on each of said shafts, means interconnecting the said pulley members and extending around the peripheral edges thereof, said means being rigidly attached to one of said pulley members and flexibly attached to the other of said pulley members, and means for imparting movement to all of said pulley members.

In testimony whereof, We hereunto aflix our signatures. I

MAURICE B. WEST. HARRY C, MAIBOHM. 

